As you may know, this device is for users who do not have a gameport to have MIDI access so they use a USB port instead.

And it seemingly works great, that is, I can play a MIDI flies in Rosegarden and they play through my electronic piano using its built in speakers, and I can also play the electronic piano and it will record nicely in Rosegarden, so MIDI in and MIDI out work fine. So what is my problem you may ask?

I can't get any MIDI sounds to go through my sound card to be able to use my computer speakers. I'm not even sure if this Roland device is designed to play through my computer speakers, so therefore I don't know if it is working right or not.

I am running a late version of KDE and it seems to be using Phonon for sound with gstreamer as a backend. I have alsa-libs installed and also have pulseaudio installed.

If I use Timidity or Fluidsynth to play MIDI files, the sounds come through my computer speakers fine.

So is this normal behavor for this Roland device to not use the computer speakers, or do I have something configured wrong?

The MIDI protocol transport only command messages, not the sound. It is like TV remote : you can change the channel, mute or enable teletext, but not hear sound on it.

If you need sound of your sound module on your sound card, you need to plug the audio outputs in the sound card inputs.
And if you need a MIDI synthesizer in your computer, take a look at timidity++ or any other solution (fluidsynth, qsynth, ...)_________________Kind regards,
Xavier Miller

Thanks for clarifying it for me Xavier. The reason I was confused is because a few years ago I had a Sound Blaster sound card where sound fonts were needed to be loaded into it and the MIDI would then play through my computer speakers. But apparently, that was because the sound card also had its own built-in tone generator that could convert the MIDI's command messages to wav, something the speakers could use. So in effect, the sound card was really doing the same thing my electronic piano is doing now. Am I correct in this assumption?

Yes, that's it : your soundcard was/has also a synthesizer.
If you want your Gentoo to do the same, you need to run a General Midi syntehsizer as timidity++ or qsynth with a general midi sound font._________________Kind regards,
Xavier Miller